侧风下桥上高速列车倾覆稳定性及临界车速的参数化研究

Parametric study on critical speed and overturning stability of high-speed train running on bridge under crosswind

基于计算流体动力学理论,采用数值模拟的方法计算高速列车通过双线简支箱梁桥时的气动力系数,考虑列车在编组中的位置、迎风侧和背风侧线路以及风偏角等因素的影响,并将数值模拟结果与风洞实验进行对比分析。根据列车倾覆系数的定义,推出对倾覆临界状态合力作用线与两侧轮轨接触斑连线交点的累计力矩计算式,从而避免求轮轨相互作用力,直接得到车速和风速的相关表达式,并据此得到求临界车速的计算方法,最后对影响列车倾覆稳定性的参数进行分析。研究结果表明:采用数值模拟计算的列车气动力系数与风洞实验结果较吻合;双线简支箱梁桥上迎风侧线路头车所受气动力最大,其侧倾临界车速最低;随弹簧刚度系数、线路曲线半径、轨道超高以及列车质量的增加,临界车速均会增加,不考虑竖向振动加速度将会过高地估计列车侧倾临界车速。

Based on the theory of computational fluid dynamics, the aerodynamic coefficients of high-speed train running on simply supported box-girder bridge with double lines were computed by numerical simulation, the train＇s position in marshaling, windward line and leeward line and wind incidence angle were considered, and the results of numerical simulation were compared with those of the wind tunnel test. The formula of accumulated moment to the intersection point of resultant force line of overturning critical situation and the line connecting two side＇s wheel-rail contact patch were deduced according to the definition of overturning coefficient of train, the formula involved with train speed and the wind velocity were acquired directly without calculating the wheel/rail interaction force, the computing method for critical speed was gained accordingly, and the parameters affecting the overturning stability of train were analyzed. The results show that the aerodynamic coefficients of train from numerical simulation and wind tunnel test agree well. The head train running on the windward line of the simply supported box-girder bridge with double lines bears the greatest aerodynamic force and its critical speed is the lowest. The critical speed increases with the increase of stiffness coefficient of spring, radius of line, track super elevation and the mass of train, and the critical speed can be overestimated if vertical vibration acceleration is not considered.